Aug. 17: Michael Phelps at the Beijing Olympics

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Phelps set records in nearly every swimming event he competed in at the 2008 Games, then also set a record for the most medals won in a single Olympic Games (previously seven, set by Mark Spitz in 1972).

Phelps set records in nearly every swimming event he competed in at the 2008 Games, then also set a record for the most medals won in a single Olympic Games (previously seven, set by Mark Spitz in 1972).